1. Warm Up Construct a segment AB.
Find the midpoint of AB and label it M.

2. Midpoint Formula
Geometry

3. Midpoint
The midpoint of a segment is the point that divides, or bisects, the segment into two congruent segments.

4. Finding the Midpoint
If you know the coordinates of the endpoints of a segment, you can calculate the coordinates of the midpoint. You simply take the mean, or average, of the x-coordinates and of the y-coordinates. This method is summarized as the Midpoint Formula

5. Midpoint Formula

6. Find the Midpoint Plot the points A(-2, 3) and B(5, -2)
Use the Midpoint Formula to find the coordinates of the midpoint of segment AB.
Graph a Segment Bisector

8. Find the Midpoint Plot the points D(3, 5) and E(-4, 0)
Use the Midpoint Formula to find the coordinates of the midpoint of segment DE.
Graph a segment bisector

10. Find the Other Endpoint of a Segment
Plot the points X(-3, 1) and M(3, -4)
The midpoint of segment XY is M. One endpoint is X. Find the coordinates of the other endpoint, Y.
Plot Y

12. Find the Other Endpoint of a Segment
Graph the points R(-1, 7) and M(2, 4)
The midpoint of segment RP is M. One endpoint is R. Find the coordinates of the other endpoint, P.
Plot P